There is much news to report.
First, we’ve found two more protractors. No. 86 (seen above) recently appeared on the staircase from Ellsworth to Highland, halfway down from its brother, No. 87 (also seen above, a rare double). No. 180 (after the jump) is at Ellsworth and Negley.
Second, Mark R took the initiative of creating a Google Map of the protractors and logging his five entries. In the coming weeks, I hope to add all the previously found protractors — sixty altogether — including pictures, locations, numbers and colors.
UPDATE (June 20, 2013): There is a new digital map, in progress, here.
Third, I’ve updated the Master List.